Refrigerant control valves

ABSTRACT

A refrigerant valve has a body with a through bore. Multiple tubes have openings aligned in a ring around a middle of the bore. The tubes lead to larger channels in the body. A needle assembly inserted through an end of the bore reciprocates a needle with a stepper motor and speed reducer to precisely control sizes of the openings. Further advancing the needle shaft after closing the openings to the tubes, engages and slides a bypass sleeve against a return spring force to open a bypass in a side of the valve body. A connector connects the bypass in a first end of the bore to outward opening holes of the channels.

This application is a continuation of application Ser. No. 12/924,702filed Oct. 1, 2010, which claims the benefit of U.S. ProvisionalApplications 61/277,988, filed Oct. 1, 2009, 61/278,269, filed Oct. 1,2009 and 61/278,503, filed Oct. 7, 2009, which are hereby incorporatedby reference in their entireties.

SUMMARY OF THE INVENTION

A refrigerant control valve has a valve body and a through bore in thevalve body. The through bore has a first end portion, a medial portionand a second end portion. Plural tubes having first and second endsextend through the valve body. Plural lateral openings in the medialportion of the through bore are connected to the first ends of thetubes. Plural channels having first and second ends extend through thevalve body. The first ends of the plural channels are connectedrespectively to the second ends of the plural tubes.

A needle assembly is mounted in the second end of the through bore. Theneedle assembly has a needle shaft with first and second ends and an endneedle on the first end of the needle shaft.

A longitudinal needle motion controller is connected to the second endof the needle shaft and is disposed with the needle assembly to move theneedle shaft in the through bore and to move the end needle in thethrough bore to selectively partially open, open, partially close, closeand obscure the lateral openings and to control refrigerant flowingbetween from them the first end of the through bore and the pluralchannels.

The valve body has an axis, a first end a second end first end portion,a medial portion and a second end portion, wherein the first end portionis generally cylindrical and the medial and second end portions aregenerally conical and funnel shaped and extend radially outward from theaxis with increasing diameters of the medial and second end portions.

The plural tubes and the plural channels are arranged at acute angleswith respect to the through bore and extend through the medial andsecond end portions.

A cap is fitted on the second end of the valve body. A sealing ring isinserted between the cap and the second end of the valve body, andfasteners connected to the cap and the second end of the valve body,compressing the sealing ring between the cap and the second end of thevalve body.

The valve body has an annular second end surface, and the annular endsurface has plural spaced connection openings at the second ends of theplural channels.

The connection openings have recesses in the second end of the valvebody. Connection tubes are inserted and sealed in the recesses.

The medial portion of the through bore is a needle chamber, wherein theneedle shaft slides.

The second end of the needle shaft is connected to a threaded shaft, andthe threaded shaft is connected to a complementary threaded sleeve. Theneedle motion controller is connected to the complementary threadedsleeve to turn the sleeve in a first direction to advance the needleshaft in the needle chamber. Turning the sleeve in a second oppositedirection moves the needle shaft in an opposite direction.

One needle motion controller further includes a stepper motor and aspeed reducer. An output on the speed reducer is connected to thethreaded sleeve to rotate the sleeve selectively in smooth smallincrements in the first and second directions.

In one embodiment, the second end of the needle shaft has a recess thatreceives the threaded shaft. A speed reducer is positioned in a firstrecess extends into the second end of the valve body. A second smallerrecess extends into the second portion of the valve body. A rotary tolinear converter is positioned in the first and second recesses. Astepper motor is connected to the speed reducer and needle assembly. Acap covers the stepper motor and holds the stepper motor toward thespeed reducer and needle assembly. A sealing ring is interposed betweenthe cap and the second end of the valve body, and fasteners connect thecap to the second end of the valve body and compress the sealing ring.

In one embodiment, a large bypass hole extends through a wall of thefirst portion of the valve body. Plural holes extend outward from firstends of the plural channels through a wall of the medial portion of thevalve body. A bypass cover having a central first end opening is fittedover the first portion and partially over the medial portion of thevalve body. A fluid connection is connected to the cover for connectingthe bypass hole in the first portion of the valve body to the pluraloutward extending holes from the first ends of the plural channels. Anannular cylindrical sleeve having open first and second ends isslideable within the through bore. The sleeve has a lateral hole forselectively aligning with the bypass hole. A sleeve travel limiter isadapted to permit movement of the sleeve between a first positionaligning the sleeve lateral hole with the bypass hole and a secondposition closing the bypass hole with a wall of the sleeve. A springinterposed between the first end of the cover and a first end of thesleeve urges the sleeve into its second position closing the bypasshole. Advancing the needle shaft toward the first end of the throughbore closes the lateral openings to the tubes and moves the sleeveagainst force of the spring into the first position of the sleeve,aligning the lateral hole in the sleeve with the bypass hole.

These and further and other objects and features of the invention areapparent in the disclosure, which includes the above and ongoing writtenspecification, with the claims and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross sectional view of the new variable volume distributor,regulator and suction valve partially closed for flow regulation.

FIG. 2 is a cross sectional view of the new variable volume distributor,regulator and suction valve fully open for maximum flow to or from thedistribution tubes.

FIG. 3 is a cross sectional view of the new variable volume distributor,regulator and suction valve fully closed for stopping flow.

FIG. 4 is a cross sectional view of the new variable volume distributor,regulator and suction valve partially closed for flow regulation.

FIG. 5 is a cross sectional view of the new variable volume distributor,regulator and suction valve fully open for maximum flow to or from thedistribution tubes.

FIG. 6 is a cross sectional view of the new variable volume distributor,regulator and suction valve fully closed for stopping flow.

FIG. 7 is a perspective view of the expansion valve and distributortaken from the side and top.

FIG. 8 is a perspective view of the expansion valve and distributortaken from the side and bottom.

FIG. 9 is a cross section of the expansion valve and distributor.

FIG. 10 is a cross section of the expansion valve and distributor with astepper motor needle and drive.

FIGS. 11 and 12 are cross sectional perspective views of the expansionvalve and distributor with the sliding needle, drive connection and astepper motor.

FIG. 13 is a cross section of a refrigerant control valve body, steppermotor, cover and seal.

FIG. 14 is an elevation of a needle assembly with a stepper motor,reduction gear case, needle, needle shaft and reciprocating drive.

FIG. 15 is an exploded view of the needle assembly, refrigerant controlvalve body, bypass housing, spring and slide in partially cross section.

FIG. 16 is an assembled view of the needle assembly, refrigerant controlvalve body, bypass housing, spring and slide partially in cross section.

FIGS. 17-20 are similar views of a liquid refrigerant control valverespectively showing the needle and slide in bypass, shut off, pressureregulating and fully open positions.

FIGS. 21-24 are similar views of a vapor refrigerant control valveshowing the needle and slide in bypass, shut off, suction pressureregulating and fully open positions.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross sectional view of the new variable volume distributor,regulator and suction valve 10 partially closed 50 for flow regulation.The valve 10 has a body 12 with a central flow channel 14.

A needle assembly 20 with a body 22 and a point 24 regulates the flowthrough channel 14 and uniformly divides the flow to the number ofmultiple smaller channels 30. The needle assembly freely slides in acylindrical receiver 16 in the body 12 and is moved precisely by astepper motor. The stepper motor controls movement of the needleassembly 20 in less than thousandths of an inch steps.

The body 12 has a frustoconical needle seat 18 which tightly seals thecomplementary sloping conical wall 28 of the needle 20. The side walls42 of the needle chamber 40 have chamfered elliptical opening ports 44leading to the smaller channels 30. The smaller channels 30 haveenlarged diameter capillary tube receivers 32 with shoulders 34 forstopping and abutting ends of the capillary tubes. The bores 36 of thesmaller channels 30 exactly match the lumens in the capillary tubes forunimpeded fluid flow. In FIG. 1 the needle assembly 20 is shown in aselected middle position 50 for regulating and metering flow.

FIG. 2 is a cross sectional view of the new variable volume distributor,regulator and suction valve 10 fully open for maximum flow to or fromthe distribution tubes. The needle assembly 20 is shown in its fullretracted position 52 for providing full opening of the ports 44 to thesmaller channels 30. Fully open ports 44 allow full flow through thecentral flow channel 14 and through the smaller channels 30.

FIG. 3 is a cross sectional view of the new variable volume distributor,regulator and suction valve 10 fully closed 54 for stopping flow. Theneedle assembly 20 is shown fully advanced, with its sloping conicalwall 28 tightly engaging the complementary frustoconical needle seat 18and preventing flow through the channels 14 and 30.

The present invention provides an all-in-one expansion and distributiondevice 10 for metering liquid heat transfer fluid into a multiple tubeevaporator. The new distributor and metering valve usually in a fullopen position 52 may be used to distribute hot vapor from a compressorto a multiple tube condenser.

A similar valve 10 in a reversed position may be used to collect cooledliquid from a condenser.

A similar all-in-one metering and distribution valve may 10 in areversed position be used to collect vapor from the parallel evaporatortubes. The needle may be positioned 50 by the stepper motor to controlpressure in the evaporator.

The new all-in-one distributor metering expansion valve may be used inany position with flow upward, downward, horizontal or angles inbetween.

The size and shape of the needle and dimensions of the channels andchambers may be precisely controlled.

From two to three or up to forty or more smaller channels may becontrolled by a single needle valve. The smaller chambers may havesplitters for directing flow to more than one capillary tube. Eachcapillary tube may have splitters for directing flow to more than onecapillary tube. Internal pressures within the system may be up to 450psi or more and up to 1200 psi for carbon dioxide refrigeration systems.

The body may be made of copper or brass, aluminum or stainless steel.The capillary tubes may be of similar material coated with flux forbrazing or secured with advanced adhesives.

There is no expansion valve up stream. The new all in one variablevolume expansion valve and distributor receives liquid refrigerant.Expansion takes place immediately, and the distributor distributes vaporand liquid to the ports 44, smaller channels 30 and capillary tubes. Thecapillary tubes deliver the vapor to the parallel microchannel tubes inthe evaporator.

FIG. 4 is a cross sectional view of the new variable volume distributor,regulator and suction valve 110 partially closed 150 for flowregulation. The valve 110 has a body 112 with a central flow channel114.

A needle assembly 120 with a body 122 and a point 124 regulates the flowthrough channel 114 and uniformly divides the flow to the number ofmultiple smaller channels 130. The needle assembly freely slides in acylindrical receiver 116 in the body 112 and is moved precisely by astepper motor. The stepper motor controls movement of the needleassembly 120 in less than thousandths of an inch steps.

The body 112 has a frustoconical needle seat 118 which tightly seals thecomplementary sloping conical wall 128 of the needle 120. The side walls142 of the needle chamber 40 have chamfered elliptical opening ports 144leading to the smaller channels 130. The smaller channels 30 haveenlarged diameter capillary tube receivers 132 with shoulders 134 forstopping and abutting ends of the capillary tubes. The bores 136 of thesmaller channels 130 exactly match the lumens in the capillary tubes forunimpeded fluid flow. In FIG. 4, the needle assembly 120 is shown in aselected middle position 150 for regulating and metering flow.

FIG. 5 is a cross sectional view of the new variable volume distributor,regulator and suction valve 110 fully open for maximum flow to or fromthe distribution tubes. The needle assembly 120 is shown in its fullretracted position 152 for providing full opening of the ports 144 tothe smaller channels 130. Fully open ports 144 allow full flow throughthe central flow channel 114 and through the smaller channels 130.

FIG. 6 is a cross sectional view of the new variable volume distributor,regulator and suction valve 110 fully closed 154 for stopping flow. Theneedle assembly 120 is shown fully advanced, with its sloping conicalwall 128 tightly engaging the complementary frustoconical needle seat118 and preventing flow through the channels 114 and 130.

The present invention provides an all-in-one expansion and distributiondevice 110 for metering liquid heat transfer fluid into a multiple tubeevaporator. The new distributor and metering valve usually in a fullopen position 152 may be used to distribute hot vapor from a compressorto a multiple tube condenser.

A similar valve 110 in a reversed position may be used to collect cooledliquid from a condenser.

A similar all-in-one metering and distribution valve may 110 in areversed position be used to collect vapor from the parallel evaporatortubes. The needle may be positioned 150 by the stepper motor to controlpressure in the evaporator.

The new all-in-one distributor metering expansion valve may be used inany position with flow upward, downward, horizontal or angles inbetween.

The size and shape of the needle and dimensions of the channels andchambers may be precisely controlled.

From two to three or up to forty or more smaller channels may becontrolled by a single needle valve. The smaller chambers may havesplitters for directing flow to more than one capillary tube. Eachcapillary tube may have splitters for directing flow to more than onecapillary tube. Internal pressures within the system may be up to 450psi or more and up to 1200 psi for carbon dioxide refrigeration systems.

The body may be made of copper or brass, aluminum or stainless steel.The capillary tubes may be of similar material coated with flux forbrazing or secured with advanced adhesives.

There is no expansion valve upstream. The new all in one variable volumeexpansion valve and distributor receives liquid refrigerant. Expansiontakes place immediately, and the distributor distributes vapor andliquid to the ports 144, smaller channels 130 and capillary tubes. Thecapillary tubes deliver the vapor to the parallel microchannel tubes inthe evaporator.

FIG. 7 is a perspective view of the expansion valve and distributortaken from the side and top. One form of the combined expansion valveand distributor 150 has a body 152 with a cylindrical section 154 and aconical section 156. An outer end of the cylindrical section has areceiver 158 with an inner shoulder 159 for receiving a heat transferfluid refrigerant line, which is permanently fixed in the receiver 158by brazing or with a permanent bonding material.

FIG. 8 is a perspective view of the expansion valve and distributor 150taken from the side and bottom. Base 160 of body 152 has an outer area162 with from three to forty or more distribution tube receivers 132.Bolts 164 hold a hermetically sealed cover 166 over a motor housing.Electric connections 168 or insulted wire holder 168 in cover 166provide connections to a stepper motor. The body 152 is made of copper,bronze, aluminum, steel or a rugged alternative material including orcovered by an insulting material. Internal tubes may be made of copper,bronze or aluminum or other material suitable for pressurizedrefrigerant and temperature ranges that may widely vary. Bolts 164 andhermetically sealed cover 166 may be made of any suitable materials.

FIG. 9 is a cross section of the expansion valve and distributor 150.The cross section shows the cylindrical section 154 of body 152 with aninlet channel 114. Channel 114 terminates outwardly in a receiver 158with a shoulder 159 for receiving and abutting a refrigerant line.Channel 114 terminates inwardly in the expanding sloping wall that isthe needle seat 118. A number of elliptical ports 144 open from theneedle chamber 140 into multiple channels 130. The channels 130 lead tocapillary tube receivers 134. Shoulders 146 of receivers 134 abut endsof the capillary tubes which are permanently fixed in receivers 132,such as by brazing or state of the art adhesives.

The needle chamber 140 has a bearing surface 141 in which needle 120slides to selectively open and close the ports 144 in closely controlledincrements or to shut off communication between the ports 144 and theinlet channel 114 when the needle 120 is fully closed against seat 118.

The hermetically sealed chambers 170, 171, 172 and 173 receive thestepper motor, reduction gears, a worm gear and a screw which move theneedle in fine adjustment. Seal 175 hermetically seals the cover 166 tothe body 152.

FIG. 10 is a cross section of the expansion valve and distributor 150with a stepper motor 180, needle 120 and drive. A stepper motor 180mounted in chamber 170 has an attached pinion 181 that drives reductiongears (not shown) mounted in chamber 171. A worm gear mounted in chamber172 moves a screw 182 connected to a shaft 183 fixed in extension 184 ofthe needle 120. Chambers 172 and 173 holds a bearing 185.

FIGS. 11 and 12 are cross sectional perspective views of the expansionvalve and distributor 150 with the sliding needle 120, drive connectionsand a stepper motor 180. Elements of the stepper motor 180 and attachedpinion 181, the seal 175 and cover 166 and the needle moving assemblyare shown. The needle 120 is in a fully open position. In actual use theneedle 120 is advanced to precisely control openings of ports 144.

Similarly combined valves and distributors 150 may be used on inlet andoutlet ends of evaporators. In the outlet end of an evaporator, spentexpanded fluid moves through the capillary tubes in the receivers 132,through the ports 144 and needle 20 chamber 140, past the needle and outthrough channel 114 and the refrigerant line connected in receiver 158.The stepper motor 180 precisely controls the needle 120 in the outletvalve 150 to control pressure in and flow through the evaporatorrefrigerant tubes.

In the exit of the evaporators and condensers the combined valves anddistributors 150 may function as combined valves and fluid combiners.

Similar combined valves and distributors 150 may be used in inlets andoutlets of condensers, except that ports 144 remain open forunrestricted through flow to cool the compressed vapor from thecompressor into a liquid in the condenser.

FIG. 13 shows an expansion valve 200, body 202 and cover 206 with asealing gasket 205. Body 202 may be made of aluminum, brass or stainlesssteel or any suitable material. The body 202 has a through bore 210 withside opening ports 212 leading to from three to forty or more tubes 214.Tubes 214 open into channels 216, which extend through connectors 218that extend from a large end 208 of the body. Connectors 218 are thintubes having proximal ends permanently fixed in receivers 219 in thelarge end 208 of the valve body 202. The connectors 218 conductrefrigerant between the channels 216 and microtubes and coils in theattached heat exchanger.

The channels 216 open laterally in an annular chamber 220 for bypass. Acylindrical portion 222 of the body 202 has an opening 221 at one sidefor a bypass connection and has a small opposite hole 226 for receivinga slide travel limiting pin.

Threaded holes 228 in end 208 receive bolts 238 extending from cover 206for engaging the cover 206 in a hermetic seal, using interposed gasket205, with end 208 of body 202. The through bore 210 has recesses 242,244 and 246 for receiving respectively a stepper motor, a reduction gearassembly, a needle drive and a bearing as shown in FIG. 2.

FIG. 14 is an assembled view of a needle assembly 250 for fitting in thethrough bore 210 and recesses 242, 244 and 246 of the valve body 202shown in FIG. 1.

The needle assembly 250 has a needle shaft 251 with an end needle 252and a recess 254 of the opposite end for receiving a threaded shaft 256.The threaded shaft is moved axially by the stepper motor 260, reductiongear assembly 262 and needle drive connection 264. The sliding bearing266 fits in recess 246 to control the movement of needle shaft andneedle into positions precisely controlled by the stepper motor andreduction gear.

FIG. 15 is an exploded view of the needle assembly refrigerant controlvalve body, bypass housing, spring and slide in cross section. As shownin FIG. 4, the needle assembly 250 is inserted in the valve body 202.The cover 206 is secured over the stepper motor 260 by bolts 238,forming a hermetic seal by compressing seal 205 in a recess.

A bypass cover 270 fits over the cylindrical portion 222 of valve body202. The bypass cover 270 has a cylindrical chamber 272 for receivingthe cylindrical end 222 of body 202. The cylindrical chamber has afrustoconical enlarged recess 274 for fitting over the conical portion224 of valve body 202 that integrally extends from the cylindricalportion.

The bypass cover 270 has bypass ports 281, 283 which are aligned withbypass ports 221, 223 in valve body 102.

Cylindrical slide 280 has a port 285 which aligns with port 281 whenslide 280 is pushed against force of compression spring 290 into aposition for alignment of port 285 with ports 221 and 281. Slide 280 hasa funnel shaped end 286 which is sloped to receive the sloped wall 253of the needle 252.

Slide 280 has an elongated opening 287 opposite port 285 which receivesan extended end of pin 288 which is fixed in hole 226 radially extendingthrough the cylindrical end 222. The inward extending end of pin 288limits movement of slide 280 to two positions. The furthest leftposition aligns port 285 with ports 221 and 281. The furthest rightposition of cylindrical slide 280 moves port 285 away from alignmentwith port 281 and shuts the bypass port, preventing bypass.

Port 283 is always aligned with port 223 in valve body 202. Port 223 hasa cylindrical circumferential chamber 220 which connects with channels216 in the valve body 202.

Ports 283 and 223 are always ready for bypass when slide 280 is movedinto the bypass position. A bypass channel 282 is connected betweenports 281 and 283 to bypass the needle valve.

FIGS. 17-20 are similar views of a liquid refrigerant control valve,respectively showing the needle shaft, needle and slide in bypass, shutoff, suction pressure regulating and fully open positions. In bypasspositions 311 of refrigerant control valve 200 as shown in FIG. 5 thestepper motor 260 and gears 262 and drive connection 264 advance theneedle shaft 251 and needle to the fully extended bypass position 311.Sides 253 of the needle 252 have pushed slide 280 to its full bypassposition 311, with spring 290 compressed. Refrigerant control fluidflows directly between port 316 at the end of bypass cover 270 andchannels 216 in the valve body 202, via chamber 220 and bypass 282.

FIG. 18 shows a shut off position 313 of refrigerant control valve anddistributor 200, in which needle 252 and shaft 251 have been retracted,allowing spring 290 to move slide 280 so that ports 285 and 281 are notaligned, shutting off the bypass 282. The needle shaft 251 issufficiently advanced so that ports 212 and tubes 214 are closed. Theentire valve 200 is shut off.

FIG. 19 shows a position 315 in which the needle shaft 251 and needle252 have been moved into a position by the stepper motor 260 topartially open the ports 212 at the end of tubes 214. Liquid refrigerantflows into port 316, strikes the needle 252 and deflects into thepartially opened ports 212 and through the tubes 214 and channels 216into microchannels and coils in a heat exchanger.

FIG. 20 shows a position 317 in which the needle shaft and needle arefully retracted to fully open ports 212 and tubes 214 leading tochannels 216 and to microtubes and coils in a heat exchanger. Liquidrefrigerant flows into port 316, strikes the needle 252 and is deflectedinto the partially opened ports 212 and through the tubes 214 andchannels 216 into microchannel tubes and coils in a heat exchanger. FIG.8 shows a position 317 in which the needle shaft and needle are fullyretracted to fully open ports 212 and tubes 214 leading to channels 216and to microtubes and coils in a heat exchanger. Liquid refrigerantunder high pressure strikes the point of needle 252 and deflects toports 212 and tubes 214.

FIGS. 21-24 are similar views of a vapor refrigerant control valveshowing the needle shaft, needle and slide respectively in bypass, shutoff, suction pressure regulating and fully open positions. FIG. 21 showsa valve 400 similar to valve 200, except for the elimination of tubes214, the enlargement of ports 412 and the inward extension of thechannel 416 to the enlarged ports 412.

In FIG. 21, which is similar to FIG. 17, the needle shaft 251 and needle252 are fully extended to push cylindrical slide to a position 311 inwhich port 285 aligns with ports 221 and 281 to place the valve 400 inbypass position 411.

Bypass ports 281 and 283 are connected to tubes 421 and 423 whichconduit the bypass fluid to another device, such as an evaporator drainpan heater coil.

FIG. 22 is similar to FIG. 18. Vapor refrigerant control valve 400 isplaced in full shut off condition 413. Needle 252 and needle shaft 251are positioned to allow slide 280 to misalign ports 385 and 281,shutting off the bypass port 281. The needle shaft 251 shuts off ports412 and channels 416.

FIG. 23 is similar to FIG. 19, except that the ports 412 are enlargedand channels 416 are extended to the larger ports. Valve 400 is usedprimarily for vapor, such as controlling release of spent cool vaporfrom an evaporator and thus controlling compressor suction pressure bycontrolling evaporator pressure. In FIG. 11 the needle 252 and needleshaft 251 are positioned to partially open ports 412, and to controlevaporator pressure and thereby suction pressure. The sloped end ofslide 280 and the sides 253 of the needle 252 form a smooth annularchannel 211 leading to or from the ports 412.

FIG. 24 shows the valve 400 fully opened by withdrawing needle 252 andneedle shaft 251 so that the ports 412 are fully open, allowing vapor tofreely pass through channels 416, ports 412 and end port 316.

As shown in all of FIGS. 15-24 end port 316 has a recess 327, in whichan end of a refrigerant line is fixed such as by brazing or by state ofthe art adhesives to connect to the line to an input of a compressor forrefrigeration.

Valves 200 are liquid refrigerant control valves which are intended tobe connected to an input of an evaporator, or to be reversed andconnected to the output of a condenser.

In the latter condenser connection, tubes 318 are connected to outletends of microchannel tubes in condenser coils. The needle and needleshaft are moved to fully bypass position as shown in FIG. 5. The ports285 and 281 are aligned to let the condenser liquid refrigerant to flowthrough tubes 218 channels 216, through bypass 282, ports 281 and 285and out through port 236.

The bypass is closed in the valve 200 at the entrance to the evaporator.Needle 252 and shaft 251 are placed in the position 315 shown in FIG. 19for controlling liquid refrigerant flow diversion by needle 252 and flowinto ports 212, tubes 214 and expand channels 218 and connectors 218when flowing into microchannel tubes and coils in the evaporator.

A similar valve 200 may replace an expansion valve to expand a smallamount of liquid to a vapor flows to the suction accumulator to controlcompressor temperature.

In the refrigeration operation valve 400 is connected to the output ofthe evaporator. The valve 400 is placed in position 415 as shown in FIG.23. The bypass is closed and spent expanded vapor passes throughconnectors 218, channels 416 and ports 412 and out through port 326 tothe suction accumulator.

In the heating and defrosting mode, a reversing valve is operated. Hotcompressed vapor from the compressor flows through vapor refrigerantvalve 400 in bypass condition 411, as shown in FIG. 21, or in fully opencondition 417, as shown in FIG. 24.

In the bypass condition hot vapor flows through ports 285 and 281 intothe tube to a drain pan heater and back through port 283 into channels416 and connectors 218 to the microchannel tubes and coils in theevaporator.

A fluid refrigerant valve 200 at the normal entrance to the evaporatoris moved to bypass condition 311 as shown in FIG. 17. The vapor whichhas been cooled and condensed to liquid in the evaporator flow from themicrochannel tubes and evaporator coils, flow through connectors 218,channels 216, annular channel 220, bypass port 283, bypass 282, port 281and aligned port 285 out through port 316 to the condenser.

Liquid refrigerant control valve 200 at the condenser is moved to aposition 315 as shown in FIG. 19. The bypass ports 385, 381 aremisaligned, shutting off the bypass. Ports 212 are slightly opened bythe needle 252 allowing the fluid to flow through tubes 214 intochannels 216 and through connectors 218 to the microchannel tubes andcoils in the condenser while expanding the liquid into vapor. The vaporis returned through the reversing valve to the compressor.

When returning the reversing valve to refrigeration, the needle in theliquid refrigerant control valve at the condenser outlet is moved to thebypass position 311 as shown in FIG. 17, the needle in the liquidrefrigerant control valve at the entrance to the evaporator is moved tometering position 315 as shown in FIG. 19, and the vapor refrigerantcontrol valve 400 at the exit of evaporator is moved to meteringposition 415 shown in FIG. 23.

While the invention has been described with reference to specificembodiments, modifications and variations of the invention may beconstructed without departing from the scope of the invention, which isdefined in the following claims.

I claim:
 1. Apparatus comprising a refrigerant control valve having avalve body, a bore in the valve body, the bore having a first endportion, a medial portion and a second end portion, the first endportion of the bore comprising a first cylinder with a first diameter,the second end portion of the bore compressing a second cylinder with asecond diameter larger than the first diameter, the medial portion ofthe bore comprising a valve seat having a frustoconical shape connectingthe first and second cylinder, plural channels extending through thevalve body, the channels having first and second ends, plural elongatedlateral openings adjacent the valve seat in the medial portion of thebore, the first ends of the channels severally connected to the lateralopenings in the medial portion of the bore, a needle assembly mounted inthe second end of the through bore, the needle assembly having a conicalportion and a cylindrical portion, the conical portion having a shapeand slope similar and complementary to the frustoconical shape of thevalve seat, a longitudinal needle motion controller connected to theneedle assembly, and disposed with the needle assembly to move theneedle in the bore and to move an end of the needle in the bore toselectively open and close the lateral openings concurrently withopening and closing the needle seat and to control fluid flowing throughthe first end portion of the bore and through the plural lateralopenings and the plural channels.
 2. The apparatus of claim 1, whereinthe valve body has an axis, a first end, a second end, a first endportion, a medial portion and a second end portion, wherein the firstend portion of the valve body is generally cylindrical and the medialand second end portions of the valve body are generally conical andfunnel shaped and extend outward from the axis with increasing diametersof the medial and second end portions.
 3. The apparatus of claim 2,wherein the plural channels are arranged at acute angles with respect tothe bore and extend through the medial portion of the valve body and thesecond end portion of the valve body.
 4. The apparatus of claim 2,further comprising a cap fitted on the second end of the valve body, asealing ring between the cap and the second end of the valve body andfasteners connected to the cap and the second end of the valve body andcompressing the sealing ring between the cap and the second end of thevalve body.
 5. The apparatus of claim 2, wherein the valve body has anannular surface and the surface has plural spaced connection openings atthe second ends of the plural channels.
 6. The apparatus of claim 5,wherein the connection openings have recesses in the second end of thevalve body and wherein connection tubes are inserted and sealed in therecesses.
 7. The apparatus of claim 2, further comprising a first recessin the second end of the valve body, a speed reducer positioned in thefirst recess, a second smaller recess in the second portion of the body,and a rotary to linear converter positioned in the first and secondrecesses, a stepper motor connected to the speed reducer, a cap coveringthe stepper motor and holding the stepper motor toward the speedreducer, a sealing ring interposed between the cap and the second end ofthe valve body and fasteners connecting the cap to the second end of thevalve body and compressing the sealing ring.
 8. The apparatus of claim2, further comprising a large bypass hole extending through a wall ofthe first portion of the valve body, plural outward extending holes fromfirst ends of the plural channels through a wall of the medial portionof the valve body, a bypass cover having a central first end openingfitted over the first portion and partially over the medial portion ofthe valve body and a fluid connection connected to the cover forconnecting the bypass hole in the first portion of the valve body to theplural outward extending holes from the first ends of the pluralchannels, an annular cylindrical sleeve having open first and secondends and slideable within the through bore, the sleeve having a lateralhole for selectively aligning with the bypass hole, a sleeve travellimiter adapted to permit movement between a first position aligning thesleeve lateral hole with the bypass hole and a second position closingthe bypass hole with a wall of the sleeve, a spring interposed betweenthe first end of the cover and a first end of the sleeve urging thesleeve into its second position closing the bypass hole, whereinadvancing the needle toward the first end of the through bore closes thelateral openings to the tubes and moves the sleeve against force of thespring into the first position of the sleeve, opening the bypass hole.9. The apparatus of claim 1, wherein the medial portion of the bore is aneedle chamber wherein a shaft of the needle shaft slides.
 10. Theapparatus of claim 9, wherein the second end of the needle is connectedto a threaded shaft, and the threaded shaft is connected to acomplementary threaded sleeve, and wherein the needle motion controlleris connected to the complementary threaded sleeve to turn the sleeve ina first direction to advance the needle in the bore and to turn thesleeve in a second opposite direction to move the needle in an oppositedirection.
 11. The apparatus of claim 10, wherein the needle motioncontroller further comprises a stepper motor, a speed reducer connectedto the stepper motor, and an output on the speed reducer connected tothe sleeve to rotate the sleeve selectively in the first and seconddirections.
 12. The apparatus of claim 10, wherein the second end of theneedle has a recess that receives the threaded shaft.
 13. Apparatuscomprising a refrigerant control valve having a valve body, a bore inthe valve body, the bore having a first end portion, a medial portionand a second end portion plural channels extending through the valvebody, the channels having first and second ends, plural lateral openingsin the medial portion of the through bore, a valve seat in the medialportion immediately adjacent the lateral openings, the first ends of thechannels severally connected to the lateral openings in the medialportion of the through bore, a needle assembly mounted in the second endof the bore, the needle assembly having a needle with first and secondends, an end needle on the first end of the needle shaft, a recess inthe second end of the needle shaft, a threaded shaft having first andsecond ends, the threaded shaft mounted in the recess in the second endof the needle shaft, a reduction gear assembly connected to the secondend of the threaded shaft, a stepper motor connected to the reductiongear assembly and disposed with the needle assembly to move the needleshaft in the bore and to move the end needle in the through bore toselectively open and obscure the lateral openings and to control fluidflowing through the first end portion of the bore and through the plurallateral openings and the plural channels.
 14. A method comprisingproviding a refrigerant control valve having a valve body with aconnection to a refrigerant, providing a bore in the valve body,providing plural channels extending through the valve body, providingplural lateral openings from the channels in the medial portion of thebore, providing a valve seat adjacent the openings in the medialportion, providing a needle assembly mounted in a second end of thebore, the needle assembly having an end needle on a first end of theneedle shaft, providing a longitudinal needle motion controller on asecond end of the needle shaft, moving the needle shaft in the bore, andselectively opening, partially closing and closing the lateral openingsand controlling refrigerant fluid flowing between the first end of thebore and the plural channels.
 15. The method of claim 14, wherein themoving the needle shaft comprises providing a stepper motor and a speedreducer, moving a threaded shaft with the speed reducer and moving theneedle with the threaded shaft.